(a) Field of the Invention
The present invention relates to a plasma display panel (PDP), and more particularly, to a PDP in which dummy barrier ribs are formed in non-display regions.
(b) Description of the Related Art
Plasma display panels (PDPs) are emerging as one of the most popular flat panel display configurations used for wall-mounted televisions and other similar display applications. Predetermined images are displayed on the PDP using a discharge mechanism of discharge cells.
The discharge cells are formed using barrier ribs that are provided in a predetermined pattern (e.g., a striped or lattice pattern) on a substrate. The barrier ribs include real barrier ribs (hereinafter referred to simply as ‘barrier ribs’), which are provided in a display region, and dummy barrier ribs, which are provided in non-display regions.
In other words, the dummy barrier ribs refer to the barrier ribs formed in non-display regions that are outside the display region, such that structural elements of the plasma display panel formed in the display region, i.e., a dielectric layer, a protection layer, address electrodes, barrier ribs, and phosphors, may be formed in the display region to a stable thickness.
However, dummy discharge cells are formed in the non-display regions by the dummy barrier ribs, and discharge occurs in the dummy discharge cells even when it does not occur in the discharge cells formed in the display region, thereby reducing picture quality. Such mis-discharge in the dummy discharge cells occurs as a result of electric charges generated in discharge cells adjacent to non-display regions passing over the barrier ribs of the discharge cells and into the dummy discharge cells in the non-display regions. These electric charges accumulate in the barrier ribs of the dummy discharge cells and cause discharge to occur in the dummy discharge cells.
To prevent this problem, a volume of the dummy discharge cells may be reduced (e.g., by removing spaces from the dummy discharge cells) such that mis-discharge does not occur. Japanese Laid-Open Patent No. 2001-35381 discloses one such configuration, in which spaces for the dummy discharge cells are filled in with the same material as the dummy barrier ribs, thereby effectively increasing the width of the dummy barrier ribs and removing spaces from the dummy discharge cells.
In all display devices including the PDP, it is desirable for the brightness to be evenly distributed over the entire display region. However, with a PDP having such dummy barrier ribs with spaces for the dummy discharge cells filled in, brightness at the edge between the display and non-display regions is greater than brightness within the display region such that overall brightness characteristics are deteriorated.
This problem is caused by the following phenomenon. In the case where the width of the dummy barrier ribs is made larger than the width of the barrier ribs inside the display region, the dummy barrier ribs tend to contract more than the barrier ribs in the display region when a paste used to form the dummy barrier ribs is baked following the deposition of the same. Hence, the volume of the discharge cells at edges of the display region is increased, thereby resulting in an uneven brightness.